LING/C SC/PSYC 438/538 Lecture 2 Sandiway Fong. Today’s Topics Did you read Chapter 1 of JM? –...
22
LING/C SC/PSYC 438/538 Lecture 2 Sandiway Fong
LING/C SC/PSYC 438/538 Lecture 2 Sandiway Fong. Today’s Topics Did you read Chapter 1 of JM? – Short Homework 1 (submit by midnight Saturday) Some slides
Todays Topics Did you read Chapter 1 of JM? Short Homework 1
(submit by midnight Saturday) Some slides from last time Today is
Perl Day! Did you install Perl on your own computer?
http://learn.perl.org/ http://learn.perl.org/
Slide 3
Application of the Day Text summarization service available on
Macs (turned off by default?) available on Microsoft Word 2008 but
not 2010 Open Text Summarizer (ots) (on Linux)
Slide 4
Application of the Day System Preferences (10.9)
Slide 5
Application of the Day Lets try it on
www.arizona.eduwww.arizona.edu
http://uanews.org/story/ua-fall-enrollment-sets-record-for-diversity-number-of-freshmen
Slide 6
Application of the Day Highlight text and control click to
bring up contextual menu
Slide 7
Application of the Day (Optional) Extra Credit for the Curious
(submit with your homework 1) Discuss whether you think the
summarizer did a good job. How do you think it works? Do you think
it should work on foreign language text? If you have a Mac or OTS
on Linux, try it
Slide 8
From last lecture
Slide 9
Examples Knowledge Which report did you file without reading?
(Parasitic gap sentence) We take for granted this process of
filling in or recovering the missing information
Slide 10
Examples Change in interpretation of embedded subject: John is
too stubborn to talk to John is too stubborn to talk to Bill
Slide 11
Examples Ambiguity where can I see the bus stop? stop: verb, or
stop: part of the noun-noun compound bus stop Diambiguate through
context (discourse or situation)
Slide 12
Examples Ambiguity where can I see the bus stop?
shutterstock.com
Slide 13
Examples Ungrammaticality *Which book did you file the report
without reading? * = ungrammatical Colorless green ideas sleep
furiously. Furiously sleep ideas green colorless. ungrammatical vs.
incomprehensible
Slide 14
Examples The human parser has quirks Ian told the man that he
hired a story Ian told the man that he hired a secretary
Garden-pathing: a temporary ambiguity tell: someone something vs.
More subtle differences The reporter who the senator attacked
admitted the error The reporter who attacked the senator admitted
the error
Slide 15
Short Homework 1 Submit your answers by Saturday midnight Email
submission (one file) to [email protected] Subject of
email: 538/438 Homework 1 Your NAME Your name at the top of the
file (I cant always tell by the email id.) Also whether 538 or 438.
Your answers to: 1.Is flying saucer an example of an idiom or
compositional in meaning? Explain your answer in terms of your
understanding of these two terms. 2.The men saw the boy with a
telescope In what way(s) is this sentence structurally ambiguous?
Explain. 3.John dislikes nearly everyone he meets In what way(s) is
this sentence referentially ambiguous? Explain.
Slide 16
Perl Day Learn Perl Books Online resources
http://learn.perl.org/ we begin with...
http://perldoc.perl.org/perlintro.html
Slide 17
Perl History invented by Larry Wall in the mid-1980s Perl =
Practical Extraction and Reporting Language It pulls together
features from many pre-existing Unix tools: efficient text
processing: awk, sed search: grep (regular expression search) shell
scripting: c-shell and others Interpreted language no compilation
phase down to machine code (cf. C) lends itself to rapid
prototyping and the writing of small programs. (Disadvantage:
slower than C.) Huge collection of Perl modules (.pm) already
written and freely available on CPAN - Comprehensive Perl Archive
Network
Slide 18
Perl Factoid Larry Wall was a linguist (UC Berkeley) from his
wikipedia entry
Slide 19
Perl Day Lets go through http://perldoc.perl.org/perlintro.html
For those who are curious, I use aquamacs as the text editor
Slide 20
Perl Day Reading Perl code (perldata): The '$' symbol works
semantically like the English word "the" in that it indicates a
single value is expected. Entire arrays (and slices of arrays and
hashes) are denoted by '@', which works much like the word "these"
or "those" does in English, in that it indicates multiple values
are expected. Entire hashes are denoted by '% (no translation) In
addition, subroutines are named with an initial '&', though
this is optional when unambiguous, just as the word "do" is often
redundant in English. Variable types: Every variable type has its
own namespace. This means that $foo and @foo are two different
variables. It also means that $foo[1] is a part of @foo, not a part
of $foo. This may seem a bit weird, but that's okay, because it is
weird.
Slide 21
Perl Day Notes from the tutorial: whitespace not always
necessary, e.g. print"Hello class!\n; is fine, but good idea to
consistently use spacing (not just for readability) variable names
must not begin with a number (use a letter), so $538students is out
$students538 is ok error messages are frequently completely
uninformative (and sometimes misleading), e.g. Bareword found where
operator expected at example.prl line 3, near "$538students"
(Missing operator before students?) Is the error associated with
the variable starting with a number? so make sure you write code
consistently. semicolon (;) is not always necessary Command
separator token semantics vs. end of command (termination) token
Best practice is to terminate every command with a semicolon
Slide 22
Exercises Practice using Perl read the documentation and run
the examples! Preparatory reading: Chapter 2 of the textbook well
be using Perls regular expression engine for this